This effect of early AGN feedback promoting a more homogeneous enrichment and shallower radial profiles, was already observed in the simulations by [1]}, for both
massive clusters and lower temperature systems.
At the group regime (\(T\lesssim 3\)  keV), they found that the flat profile of iron abundance in the outskirts of the simulated groups was in contrast with the observational results by [2]}, employed for comparison .
The simulation results are instead more in line with recent observational data, e.g. by [3]} and [4]}.
Already in [1]}, it was shown that also the
the silicon-to-iron abundance ratio in simulations was found to be flat out to large distances from the center in groups, as well as in clusters, indicating also a similar contribution of SNIa and SNcc to the gas metal enrichment.
A relatively flat silicon-to-iron ratio was also confirmed by independent results obtained by [6]} on a set of simulated galaxy groups extracted from the OverWhelmingly Large Simulations (OWLS) project [7]}, despite finding typically more pronounced radial gradients of the IGrM metallicity.
Several independent simulation studies converge on the idea that energy feedback solely due to supernova winds typically produces clumpier distributions of \(\alpha \) -elements, like oxygen or silicon, and steeper, decreasing radial metallicity profiles.
The reason for the different metal distribution can be related to the origin of the \(\alpha \) -elements, mostly produced by SNcc and therefore confined in the vicinity of star-formation sites, where they can be efficiently locked back into newly formed stars unless an efficient mechanism intervenes to fastly distribute them far enough.
The steeper profiles in absence of AGN feedback was also mildly noted in [8]}, although the galactic outflow model used in their cosmological simulations was able to reproduce the global iron content in group-size haloes, together with various observations of cosmic chemical enrichment. Those authors concluded as well that an efficient outflow mechanism, able to displace pre-enriched gas out of galaxies, must be in place already at early times, in order to explain the observed chemical enrichment of the inter-galactic medium at \(z\sim 6\)  .
